Rheological investigation of effect of high temperature on geothermal drilling fluids additives and lost circulation materials

Lost circulation occurs when the returned fluid is less than what is pumped into the well due to loss of fluid to pores or fractures. A lost-circulation event is a common occurrence in a geothermal well. Typical geothermal reservoirs are often under-pressured and have larger fracture apertures. A severe lost-circulation event is costly and may lead to stuck pipe, well instability, and well abandonment. One typical treatment is adding lost-circulation materials (LCMs) to seal fractures. Conventional LCMs fail to properly seal fractures because their mechanical limit is exceeded at elevated temperatures. In this paper, parametric studies in numerical simulations are conducted to better understand different thermal effects on the sealing mechanisms of LCMs. The computational fluid dynamics (CFDs) and the discrete element method (DEM) are coupled to accurately capture the true physics of sealing by granular materials. Due to computational limits, the traditional Eulerian–Eulerian approach treats solid particles as a group of continuum matter. With the advance of modern computational power, particle bridging is achievable with DEM to track individual particles by modeling their interactive forces between each other. Particle–fluid interactions can be modeled by coupling CFD algorithms. Fracture sealing capability is investigated by studying the effect of four individual properties including fluid viscosity, particle size, friction coefficient, and Young’s modulus. It is found that thermally degraded properties lead to inefficient fracture sealing.

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Investigation of High-Temperature Fluid Loss Control Agents in Geothermal Drilling Fluids

10.2118/10736-ms ◽

1982 ◽

Cited By ~ 1

Author(s):

Leroy L. Carney ◽

Necip Guven

Keyword(s):

High Temperature ◽

Fluid Loss ◽

Drilling Fluids ◽

Geothermal Drilling ◽

Loss Control

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Study on Lost Circulation in an Extended Horizontal Well in Cuba

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.765-767.266 ◽

2013 ◽

Vol 765-767 ◽

pp. 266-269

Author(s):

Cheng Luo ◽

Xiao Chun Cao ◽

Yi Qin ◽

Bei Ren Li

Keyword(s):

Horizontal Well ◽

Drilling Fluids ◽

Cement Slurry ◽

Processing Methods ◽

Lost Circulation ◽

Eastern Cuba ◽

Controlling Measures ◽

Lost Circulation Materials

An extended horizontal well was to be drilled in the eastern Cuba. Because lost circulation of drilling fluids and cement slurry could take place in the target sections, the controlling measures were studied. There were several processing measures. And Lost circulation materials (LCM) could be used when the loss of circulation happened. The test and processing methods were also introduced.

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Wood Fibre Based Lost Circulation Materials

Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology ◽

10.1115/omae2018-77662 ◽

2018 ◽

Author(s):

Arild Saasen ◽

Helge Hodne ◽

Egil Ronæs ◽

Simen André Aarskog ◽

Bente Hetland ◽

...

Keyword(s):

Fibre Type ◽

Drilling Fluid ◽

Wood Fibre ◽

Fluid Loss ◽

Drilling Fluids ◽

Lost Circulation ◽

Bottom Hole Assembly ◽

Induced Fractures ◽

Fine Wood ◽

Lost Circulation Materials

In this paper both a coarse and fine wood fibre type of Lost Circulation Material (LCM) is tested in the laboratory. It is shown how these fibre treatments work. The fibre type is partially oil wetting making them suitable for application in oil based drilling fluids. The fine material helps stopping small drilling induced fractures, while the coarse helps stopping lost circulation into several natural fractures or coal or conglomerate formations. In the article, the selection of wood fibres is described in more detail. Testing of the fine materials were conducted conventionally by pumping drilling fluid volumes with LCM onto slotted disks in fluid loss apparatuses. The coarse fibres are too large to be tested in these apparatuses. Therefore, gravel with grain diameter around two centimetres was filled into transparent cylinders. The pore throats created by these gravel particles were above half a centimetre. For both of these LCMs the experiments show the sensitivity of the LCM concentration in the drilling fluid to stop the lost circulation. Also, it is shown the effect of the LCM on viscous properties of the drilling fluids. Not all LCMs can be pumped through the bit. The article describes the need for circulation subs in the bottom hole assembly (BHA) to hinder the LCM blocking the entire BHA.

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The Effects of Temperature on Rheology Properties and Filtrate after Using Lemongrass as Lost Circulation Materials for Oil Based Drilling Mud

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.911.243 ◽

2014 ◽

Vol 911 ◽

pp. 243-247 ◽

Cited By ~ 1

Author(s):

N.A. Ghazali ◽

T.A.T. Mohd ◽

N. Alias ◽

M.Z. Shahruddin ◽

A. Sauki ◽

...

Keyword(s):

High Temperature ◽

Filter Press ◽

Effect Of Temperature ◽

Drilling Mud ◽

Lost Circulation ◽

Water Based ◽

Different Temperatures ◽

Effects Of Temperature ◽

Mud Loss ◽

Lost Circulation Materials

Lost circulation materials (LCM) are used to combat mud loss to the reservoir formation which can cause problems during drilling operation. Difficulties in handling and costly are those challenges faced by drilling operator. Mostly LCM can work better in water based mud compared to oil based mud due to characteristic of LCM itself. Nowadays, most of operator interested in the ultra-deep water due to the limitation of reservesand deals with high temperature and high pressure conditions.Oil based mud (OBM) is more preferable in high temperature conditions compared to water based mud hence a laboratory study was carried out to investigate the effect of temperature on the performance of lemongrass with different sizes in oil based mud. The oil based mud was formulated and tested with three different temperatures which are 250oF, 275oF and 350oF. The lemongrass LCM was prepared with three different sizes which are 150 microns, 250 microns and 500 microns. The sizes distribution of LCM is one of the main contributors to the success of LCM in the formation. The oil based mud samples were tested using Fann Viscometer to determine rheology properties and HPHT Filter Press to investigate the amount of filtrate. It was found that different temperatures and sizes have great effects on the lemongrass LCM in the oil based mud. The optimum temperature for lemongrass LCM is 275oF and with the sizes of 250 microns.

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Screening of Lost Circulation Materials for Geothermal Applications: Experimental Study at High Temperature

Journal of Energy Resources Technology ◽

10.1115/1.4053071 ◽

2021 ◽

pp. 1-16

Author(s):

Cesar Vivas ◽

Saeed Salehi

Keyword(s):

Particle Size ◽

High Temperature ◽

Thermal Degradation ◽

Particle Size Distribution ◽

Size Distribution ◽

Granular Materials ◽

Lost Circulation ◽

Key Factor ◽

Sealing Pressure ◽

Lost Circulation Materials

Abstract This study presents a laboratory experimental research to determine the characteristics of lost circulation materials (LCM) capable of addressing thermal degradation, providing bridging, and sealing in geothermal conditions. Eleven different materials were tested; Walnut Fine, Walnut Medium, Sawdust, Altavert, Graphite Blend, Bentonite Chips, Micronized Cellulose (MICRO-C), Magma Fiber Fine, diatomaceous earth/amorphous silica powder (DEASP), Cotton Seed Hulls, and a Calcium Carbonate Blend. The filtration and sealing pressure of the LCMs were measured with HPHT equipment up to 149°C (300°F). Besides, the particle size distribution (PSD) of fine granular materials was measured. The results show that the performance of some LCM materials commonly used in geothermal operations is affected by high temperature. Characteristics such as shape and size made some materials more prone to thermal degradation. Also, it was found that the PSD of LCMs is a key factor in the effectiveness of bridging and sealing fractures. The results suggest that granular materials with a wide particle size distribution PSD are suitable for geothermal applications.

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Mitigation of Lost Circulation in Oil-Based Drilling Fluids Using Oil Absorbent Polymers

Materials ◽

10.3390/ma11102020 ◽

2018 ◽

Vol 11 (10) ◽

pp. 2020 ◽

Cited By ~ 6

Author(s):

Hanyi Zhong ◽

Guangcheng Shen ◽

Peng Yang ◽

Zhengsong Qiu ◽

Junbin Jin ◽

...

Keyword(s):

Suspension Polymerization ◽

Fluid Loss ◽

Drilling Fluids ◽

Fluid Viscosity ◽

Lost Circulation ◽

Fracture Sealing ◽

Oil Absorbent ◽

Lost Circulation Materials ◽

Filtration Properties ◽

Absorbent Polymer

In order to mitigate the loss circulation of oil-based drilling fluids (OBDFs), an oil-absorbent polymer (OAP) composed by methylmethacrylate (MMA), butyl acrylate (BA), and hexadecyl methacrylate (HMA) was synthesized by suspension polymerization and characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and scanning electronic microscopy (SEM). The oil-absorptive capacity of OAP under different solvents was measured as the function of temperature and time. The effect of the OAP on the rheological and filtration properties of OBDFs was initially evaluated, and then the sealing property of OAP particles as lost circulation materials (LCMs) was examined by a high-temperature and high-pressure (HTHP) filtration test, a sand bed filtration test, a permeable plugging test, and a fracture sealing testing. The test results indicated that the addition of OAP had relatively little influence on the rheological properties of OBDF at content lower than 1.5 w/v % but increased the fluid viscosity remarkably at content higher than 3 w/v %. It could reduce the HTHP filtration and improve the sealing capacity of OBDF significantly. In the sealing treatment, after addition into the OBDF, the OAP particles could absorb oil accompanied with volume enlargement, which led to the increase of the fluid viscosity and slowing down of the fluid loss speed. The swelled and deformable OAP particles could be squeezed into the micro-fractures with self-adoption and seal the loss channel. More important, fluid loss was dramatically reduced when OAP particles were combined with other conventional LCMs by a synergistic effect.

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Laboratory Study on a New Composite Plugging Material with High Bearing Strength and High-Temperature Resistance

Journal of Chemistry ◽

10.1155/2019/1874617 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Xiaoming Su ◽

Zhanghua Lian ◽

Hanqiao Xiong ◽

Yuan Yuan ◽

Junwei Fang

Keyword(s):

High Temperature ◽

Drilling Fluid ◽

Carbonate Reservoir ◽

Invasion Depth ◽

Temperature Resistance ◽

Lost Circulation ◽

Bearing Strength ◽

High Temperature Resistance ◽

Acid Solubility ◽

Lost Circulation Materials

The reservoir in the Central Tarim Basin is a typical high-pressure fracture-vuggy carbonate reservoir with high temperatures, which easily leads to drilling fluid losses and the high-temperature carbonate. The conventional lost circulation materials (LCMs) cannot meet the reservoir. To resolve this problem, a rigid particle with high-temperature resistance, high acid solubility, and high rigidity was developed, tested, and evaluated. According to bridge rules of 1/2–2/3 opening degree of formation fracture, the formulation experiments of GZD and other lost circulation materials were conducted and a novel composite lost circulation material (LCM) was completed. Lastly, we investigated the compatibility of LCM and mud in site though compatibility experiment, analyzed the plugging effect of the system for fracture and vuggy by laboratory static lost circulation simulation and evaluation and sand-bed plugging experiments, respectively. The results show that compared with the conventional rigid lost material, the value of high-temperature resistance is more and acid solubility is over 98%. Also, it can work well with other fiber materials (E), variable filling particles (F and G), and superfine filling particles (H) and form a novel plugging material, named MGY-I, whose temperature resistance value is more than 473.15 K, the bearing strength is over than 9 MPa, the mud filtrate invasion depth of sand bed made from coarse particles (10∼20 mesh) is only 3.0 cm within 30 minutes, and the invasion depth is less than 1 cm within 30 minutes when the sand bed is made from 80∼100 mesh. The optimal concentrations of rigid granule, lignin fiber, elastic particle, and superfine calcium carbonate are 8% (A : B : CD = 2 : 1 : 1), 0.5%, 6%, and 1%, respectively. And, the plugging function of “GZD-rigidity bridge and filling, fiber network and deformable filing” is better exerted on the formation fracture with a high loading capacity and a high-temperature resistance.

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